Field of the Invention
This invention relates to an apparatus and to a method. More specifically, this invention concerns itself with a unique forceps-like assembly adapted for use in conjunction with endoscopic instruments; and a method for the grasping/manipulation of objects within a bodily cavity by such endoscopic instruments.
Description of the Prior Art
The advent of flexible endoscopic instruments has made possible the invasive, non-surgical examination of the remote areas of the gastrointestinal tract. In addition, various surgical and manipulative accessories have also been developed for use in conjunction with such endoscopic instruments to perform minor surgical procedures and/or the removal of obstructive deposits from remote areas now made accessible by such endoscopic instruments. These accessories have, thus, expanded the versatility of such instruments and provide the physician with an alternative to the more traditional, and decidedly more traumatic, surgical procedures.
One common accessory which has greatly enhanced the utility of endoscopic instruments, is forceps. Typically, this accessory can consist of an elongated shaft having a plurality of resilient fingers disposed on one end thereof. These fingers can be manipulated or alternatively are biased in a spaced apart relationship. The opposite end of the shaft is fitted with an actuator mechanism which enables both extention and operation of such fingers in the field of operative interest. This accessory generally consists of one other component, namely a tubular element or sheath, through which the elongated forceps shaft can be extended or withdrawn. This accessory is generally initially prepositioned within the channel provided therefor in an endoscopic instrument, the endoscopic instrument inserted by the physician into the patient and the distal end of the instrument manipulated so as to provide the physician with visual access to the field of operative interest. The physician may thereafter extend/advance the forceps from its channel within the endoscope so as to position the fingers thereof around an object to effect either its manipulation or eventual grasping and removal. The operation of the forceps of the type described hereinabove is traditionally dependent upon axial motion of the forceps relative to the endoscope to achieve opening and closing the grasp of these fingers. As is readily appreciated, where the forceps are used in conjunction with relatively long endoscopic instruments, typically on the order of two to three feet, the physician is required to initially position the forceps in the manner described above and thereafter further advance the endoscopic instrument into the patient in the direction of the tissue/deposit so as to maintain the fingers of the forceps in a stationary position relative to the object which is to be grasped. As is evident from the foregoing description, the axial movement of the forceps assembly into the endoscope to effect closure thereof will cause the forceps to recede out of range of grasping distance of the object.
U.S. Pat. Nos. 4,003,380; 4,174,715; 4,085,743 all disclose various accessory tools suitable for use in endoscopic instruments. Each of the devices disclosed by these patents reveals a forceps assembly comprising of an elongated shaft and two concentrically arranged tubular members. In each of the accessory tools, an elongated shaft (either disposed within a tubular member and the manipulative/operative components of the tool) is extended from the tube or withdrawn into it as a means of manipulating the functional implement of each such tool. In virtually all instances of operation of the devices described in these patents, compensatory axial motion of the endoscope is required to maintain the functional implement of the tool stationary relative to the site of operative interest.
As is evident from the foregoing discussion, all the prior art devices in which a manipulative instrument is used and which requires extention and retraction of the grasping element into a tubular member for the articulation thereof, are limited in their utility, and often times difficult to operate, because such extention and retraction results in a recession of the tool from the site of operative interest. This recession of the tool generally places the object out of range of the grasping elements of the tool. Absent compensatory movement of the endoscope shaft, the tool cannot remain stationary, vis-a-vis, the field of operative interest. Where such accessories are used in endoscopic instruments of substantial length, the achievement of such compensatory motion is greatly complicated. Thus, there is a continuing need for an accessory forceps which can be operated essentially independent of axial movement of the endoscopic shaft and which is otherwise compatible with the existing operation of the endoscope.